One of my mentors got hold of me when I was about five years old. He was a piano teacher. In the group of people who have been guides he has a special place. He was called Ronald Center, and the odd thing is that you wouldn't know how influential he was if you listened to my piano playing (not something I like people to do, for reasons I shall keep private). He was slightly eccentric, a brilliant musician and - quietly and determinedly - a composer.

When I began to visit him on Thursday nights, in his slightly austere and handsome house in Aberdeenshire, he was quite scary. I didn't practise hard enough; I didn't concentrate; my fingers were never properly exercised into shape. But over the years I came to love drinking at his well. He would talk about composers he admired, and why. As I got older - the lessons went on until I left home for university - our conversations began to take up more time than my playing. They were enthralling - about books, opera, ideas, his feelings about music. Sometimes politics too.

Before the pupils started to come, and after they'd gone, he would compose. The output was modest, but there is, for example, a rich piano sonata, string quartets, a divertimento for strings, the bare bones of a symphony and many song settings. Some were performed in his lifetime - he died in 1973, aged 60 - but he lived with the frustration of a talent that never quite reached its full flowering.

My good luck was to get some understanding of how important music might be, how it could take you away from the here-and-now, and perhaps also how the artistic temperament could conceal honesty and self-criticism. Mr Center - anything less formal would have been unthinkable - was devoted to his craft, and wanted to teach because he understood there was a secret that had to be passed on.

Long after he died I opened a cardboard box in the National Library of Scotland which contained many of his notes and manuscripts. I came across a piece of paper that seemed familiar - a cyclostyled programme for the annual concert his pupils used to put on in a local church hall for their parents, a modest occasion but terrifying for us all. On the back of the programme was a scribbled staff and stave and a snatch of his music. On the other, in the typed list of performers in the concert, was my own name. I was five or six and listed as performing, I think, a cowboy tune. That's about half a century ago. They were fun nights, and I owe Mr Center a great deal. He was a better teacher than he knew.

·James Naughtie, who presents the Today programme on BBC Radio 4, was talking to Deany Judd. His new book, The Making of Music, is published by John Murray